Moon Flower: Rising Tropical White Morning Glory

Moon flower can be a stunning addition to any flower garden. This vining plant is a fast grower that will readily attach itself to any type of support structure and create a vertical wall of flowers in your garden. They produce beautiful white flowers that are rounded and can be the size of a salad plate (about 6 inches in diameter). Although the white variety is probably the most popular they do come in other colors such as pink, purple and blue. 

Moonflower is actually a close relative to the sweet potato vine (Ipomoea batatas). Unlike its Ipomoea sibling, I. alba is not edible; like most morning glory species it produces seeds that can be mildly toxic to animals. (Technically speaking, sweet potato seeds shouldn’t be consumed by dogs/cats/horses either, although they’re slightly safer!) On the bright side, it’s fairly easy to keep pets away from moonflower seeds.

There are two other close relatives that fall under the greater category of moon flowers too: Ipomoea leptophylla (aka bush moonflower) and Ipomoea violacea (beach moonflower or sea moonflower, depending on who you talk to). Growing moonflowers is quite easy, and below we’ll discuss their care requirements. 

Good Products At Amazon For Growing Moonflowers:

Quick Care Guide

White morning gloryMoonflower is also called tropical white morning glory. Source: Scott Zona

Common NameMoonflower plant, tropical white morning glory, moon vine
Scientific NameIpomoea alba
FamilyConvolvulaceae
Height & SpreadUp to 4ft wide and 8ft tall
LightFull sun
SoilLoose, well-drained soil
WaterOne to two deep waterings per week
Pests & DiseasesHornworms, black rot

All About The Moon Flower

Ipomoea alba, also known as the moonflower plant, moon vine, or tropical white morning glory is often confused with Datura which is similar in appearance, but a completely different species and plant type. Daturas exist in the Solanaceae family with deadly nightshade. Datura is sometimes mistakenly called moonflower but is more often referred to as thornapples, jimsonweeds, and devil’s trumpets. Datura species are highly hallucinogenic, whereas moonflower is not. Another way to distinguish between the two is that Datura flowers bloom during the daytime, whereas moonflower will only begin to bloom in the late afternoon into the night. Moonflowers will begin to close as the sun rises. They may stay open on cloudy days, however. 

Moonflower plants originated in tropical and subtropical regions of northern and South America. For this reason, moonflower vines grow best in southern zones. They can be grown in a perennial flower garden in USDA zones 9-12 but will be grown as annuals in all other zones. Moon flowers bloom along long vines that put out dark green heart-shaped leaves. These moonflower vines will sprawl along the ground unless they are given a structure to climb. 

Types Of Moon Flower Plants

Moonflower budsAn excellent side view of moonflower buds. Source: Starr

There are two other types of moonflowers that are a part of the Ipomoea species: bush moonflower and beach moonflower. Bush moonflower, as its name suggests, does not grow as a vine but rather forms a bushy clump. Instead of the standard heart-shaped leaves, they have long slender, thin leaves. Beach moonflower or sea moonflower has thicker leaves and prefers coastal environments such as mangrove swamps. 

Moon Flower Care

Growing moonflower plants is very easy given they are a voracious climbing vine and can even be considered a weed in some areas. Moonflower vines grow under a variety of conditions, but we’ll discuss the optimal conditions needed to get the most flowers to bloom. 

Sun and Temperature

Moonflower plants do best when planted in an area of the garden in full sun that receives at least 6-8 hours of direct sunlight per day. These tropical flowers can be grown as a perennial in USDA zones 9-12. They will be grown as an annual in all other zones. Moonflower vines can also be grown as far north as USDA zones 3-4 as long as they are grown during the warmest mid-summer months. That being said, the ideal outdoor temperatures for moonflowers are between 65-85 degrees Fahrenheit. Once nighttime lows are reliably in the 60s then that is a good time to direct sow your moonflower seed. In colder climates with shorter growing seasons, you may want to start your moonflower seeds indoors 6-8 weeks before you plan to transplant them out. 

Water and Humidity

Ipomoea alba foliage and flowersIpomoea alba foliage and flowers. Source: Starr

The best time of day to water your moonflower vine is in the early morning which will allow the water to penetrate before the sun has a chance to evaporate it from the soil. Moonflower plants can survive in a variety of conditions and are relatively drought-tolerant, however, a deep watering one to two times per week will yield the most growth and more blooms. Water at the base of the vines with a soaker hose. Since the moonflower vine is native to tropical climates it prefers a fairly high humidity level. However, it will tolerate dry air as long as it is kept well watered. 

Soil

When planting moonflowers in your gardens it is important to choose a site with loose, well-drained soil. If your native soil is not ideal then you may choose to grow moonflower plants in a container instead. This way, you can more easily control the soil conditions and make adjustments as needed. They can be grown in large containers, at least 12 inches deep, with plenty of drainage holes at the base. The moonflower vine can survive poor soil conditions and generally doesn’t need anything other than good drainage. They will not, however, tolerate acidic soil and do their best in neutral soil. 

Fertilizing Moon Flower

Since moonflower plants are a vigorous vine, it’s not absolutely necessary to fertilize them. However, if you choose to give it a boost, then there are a few things to note. Too much nitrogen fertilizer will boost the growth of the foliage but will limit the number of times moonflowers bloom. Half-strength high phosphorus fertilizer is the better choice to encourage more blooms on your moonflower vine. A liquid fertilizer applied in early summer will help boost your blooms for the remainder of the season. 

Pruning & Training Moon Flowers

Moonflower plants grow best on a support like a trellis, fence, or pergola. Plant them alongside the base of your support structure and as the plants grow tall enough, lean them over to your trellis and gently attach them with a plant twist tie or string. This will encourage them to reach in this direction. They will eventually grow tiny tendrils, grab onto the structure on their own, and continue to climb. 

When moonflower plants are grown as a perennial, they should be pruned back to the ground in the autumn and the roots protected with mulch over the winter. Your plant will come back to life in the spring. When grown as an annual you can cut back the vines as they grow to control the spread or give an overall shape as needed and desired. 

Ipomoea alba seed podsIpomoea alba seed pods are quite large. Source: Cerlin Ng

Propagation

Although moonflowers are grown as an annual in most areas, they will readily self-seed and keep coming back year after year once they’ve established a patch in your gardens. You can also collect the moonflower seeds at the end of the season and plant them in a more intentional row or pattern or move them to other areas. The white flowers only bloom once. After the flower has wilted, you will then see the seed pods begin to form in its place. Allow the seed pods to fully mature on the plant and then remove them to dry. The following spring it will be time to plant your seeds! Since moonflower seeds have such a thick seed coat, there are a few tricks to help aid in higher germination rates. Be sure to nick the outer layer of the seeds’ seed coat with a nail file and soak the seeds overnight in warm water. Choose your planting site and keep seeds evenly moist until they begin to sprout new plants. 

Moonflower can also be propagated via cuttings, although this method is less reliable. Take a cutting of the vine just below the leaf node and remove foliage on the bottom 2-3 inches of the stem. Place the stem in a glass of water, and you should see roots begin to form in a few weeks. Once the roots have appeared, you may transplant them to your planting site outdoors, or they can even be grown indoors in a pot as long as they receive enough sunlight. 

Troubleshooting Moon Flower

Moonflower with slight damageSlightly-damaged moonflower and leaves. Source: Dinesh Valke

As mentioned above, moonflower vines are relatively easy to grow and care for as long as they are provided with weekly deep waterings and well-draining soil. There are a few issues worth noting, however. 

Growing Problems

A lack of sunlight can drastically reduce the number of blooms and that’s the reason that we’re growing this vine in the first place! If you notice lackluster vine growth and no blooms, then consider the placement in your garden. They may need more sunlight! This is one plant that will not tolerate being planted in ground in part shade. 

Pests

As previously mentioned, moonflowers are a great way to attract nocturnal pollinators to your garden. However, that does come with a potential downside. Moonflowers are known to attract hummingbird moths to your garden, which are beneficial pollinators. The hummingbird moth larval stage are caterpillars referred to as hornworms and have a very similar appearance to the dreaded tomato hornworm. However, they are not the same and do not cause the same destruction to your plants! Hornworms will chomp on foliage but are not nearly as destructive as tomato hornworms. 

That being said, moonflowers can also attract the five spotted hawk moth, the species whose eggs produce the dreaded tomato hornworm! It’s best to learn how to identify these moths and all stages of their life cycle so that you can appropriately dispose of potential pests as you come across them. I’ve found that checking the undersides of leaves regularly will help with pest management, especially if you begin to notice tiny holes in your leaves. Spraying your plants with BT spray can reduce the larval numbers. Remove debris and leaf litter at the end of the season to avoid providing the caterpillars with the perfect overwintering site. Tomato hornworms will overwinter in their chrysalis stage. 

Diseases

Black rot is a bacterial disease that can affect moonflowers in hot and humid weather. It appears as yellowish-orange, V-shaped markings on the outer edges of the leaves and eventually causes the leaves to fall off. To prevent this disease, don’t crowd your plants together. Disease problems are not frequent, and you can make sure they have good air circulation as a preventative measure. Make sure they are planted in your garden with adequate space, and selectively prune when needed. There are no treatments for black rot once the disease has occurred. However, copper fungicide that is labeled for use on cruciferous vegetables may help limit additional disease development and spread even though this disease is caused by a bacterium.  

Frequently Asked Questions

Moon flowerMoon flower is a lovely night bloomer. Source: Scott Zona

Q: How should I use moonflower in the landscape?

A: This climbing vine does best when grown on a trellis and can make a stunning addition to an arch at the entrance to your garden. An arch or arbor with morning glories growing on one side and moonflowers on the other will provide you with blooms durin the day and at night too. The morning glories on one half will bloom in the morning and then in the late afternoon and into the evening, the moonflowers will bloom on their half of the trellis.

Q: Can moonflowers grow in pots?

A: Yes, they can be grown in pots in the garden as long as they are sufficiently deep enough for the root system (at least 12 inches deep). 

Q: Do moonflowers come back every year?

A: They can be grown as a perennial vine in USDA zones 9 and up. In lower zones, they will be annuals, although they will readily self-seed and can come back year after year via seeds that have dropped from the previous year’s moonflower plants. 

Q: Are moon flowers poisonous to touch?

A: They are not! Ipomoea is not toxic to people, small children, or pets, however, it bears a striking resemblance to Datura which is also sometimes referred to as moonflower and can have hallucinogenic effects if ingested. 

Q: Can moonflower get you high?

A: No, moonflower can’t get you high. As mentioned above, this is a common misconception that comes from the confusion between Ipomoea alba and Datura. 

Q: What is special about a moonflower?

A: It has beautiful white flowers surrounded by deep green heart-shaped leaves. There are very few nocturnal blooms and these can be used to help attract nighttime pollinators to your garden which can be beneficial if you have other nocturnal blooms that you wish to be pollinated like dragon fruit. 

Q: Are moon flowers illegal?

A: Ipomoea alba is not illegal. Growing moonflowers is not illegal either.

Q: Do hummingbirds like moonflowers?

A: Since they are night-blooming, it’s unlikely that hummingbirds would be out and about while the flowers are in bloom. Hummingbird moths, however, will definitely be attracted to your garden whenever these flowers are in bloom. 

Q: Can you smell moonflower?

A: Yes, they have a sweet fragrance similar to orange blossoms. 

Leave a comment